ARLA/CLUSTER: Joe Taylor (K1JT) divulga novo modo digital FT4 , duas vezes e meia mais rápido que o FT8.

[João Costa > CT1FBF]

New digital mode FT4

*Joe Taylor K1JT* has announced a new digital mode, *FT4*, which is 2.5
times faster than FT8

FT4 is an experimental digital mode designed specifically for radio
contesting.  Like FT8, it uses fixed-length transmissions, structured
messages with formats optimized for minimal QSOs, and strong forward error
correction.  T/R sequences are 6 seconds long, so FT4 is 2.5 × faster than
FT8 and about the same speed as RTTY for radio contesting.

FT4 can work with signals 10 dB weaker than needed for RTTY, while using
much less bandwidth.

FT4 message formats are the same as those in FT8 and encoded with the same
(174,91) low-density parity check code.  Transmissions last for 4.48 s,
compared to 12.64 s for FT8.  Modulation uses 4-tone frequency-shift keying
at approximately 23.4 baud, with tones separated by the baud rate.  The
occupied  bandwidth (that containing 99% of transmitted power) is 90 Hz

Further information on FT4 is at
http://physics.princeton.edu/pulsar/k1jt/FT4_Protocol.pdf
-------------- próxima parte ----------
Um anexo em HTML foi limpo...
URL: http://radio-amador.net/pipermail/cluster/attachments/20190423/12cf097c/attachment.html